Mash Monitor

Jer · 02-17-2007, 07:14 PM

Right before I started my first AG batch (just finished my 3rd), I dropped and shattered my thermometer, luckily I had a thermocouple probe sitting my car that I borrowed from work (used it to test the coolers temperature loss)... Unfortuantely, my temps were all over the place before I got them to where I wanted too (water too hot or not hot enough..etc), so I thought it might be a cool idea to log those temperatures to see how well I was hitting my target temps for each brewing session...

So I came up with the following "Mash Monitor"... I'm still working out some of the bugs, and the temperature sensors (thermistor) need a bit of work with accuracy and stability (temps change too much, too fast.. maybe I need to attach them to a piece of metal or something??)

Anyways, so I have 2 sensors, one to monitor the water on the stove, and one for the mash in the cooler.. There are a couple of threshold alarms, and also alarms for each step, and a few other 'features'... Here's a screen shot of the program:

Here's what my setup looked like:

And then here is the hardware... It's from an old project, so there's a bunch of other junk on there that's not needed... If/when I do a layout for it, I think I can get it to probably about 1/8 to 1/4 of this size...

**the_bird** · 02-17-2007, 07:30 PM

Dude, that is so friggin' cool. Damn, you're a smarter guy than I am; I'm a single infusion, set-and-forget kind of guy. What strikes me as odd, though, is the magnitude of the drop with that cooler. I have the exact same one, and I've had, at most, a one degree drop in temp over an hour (two degrees if I open and stir frequently). Looks like in your second stage, you dropped from 154 to 148, which is much more than I *thought* I was experiencing (maybe my probe's not as accurate

)

Anyway, sweet setup!

Erbium:YAG · 02-17-2007, 07:43 PM

Pretty cool. There's nothing like high tech and beer combined. As far as the thermistors go, you might have a more linear response if they were mounted to a piece of copper. Nice work.

**kladue** · 02-20-2007, 09:06 PM

Nice looking display screen, is this a visual basic application that you have built yourself to interface with the board in the picture. Do you have any plans to expand the scope of the application to include pumping and valve control in an expanded system?

Jer · 02-20-2007, 09:46 PM

Quote:

Looks like in your second stage, you dropped from 154 to 148, which is much more than I *thought* I was experiencing (maybe my probe's not as accurate )

Actually, unfortunately, that wasn't the actual screenshot of it in action, I took that one when I was testing the software out, so I hope I don't lose that much heat either... When I originally tested the cooler, I brought 2 gallons of water to 155 after preheating the cooler with boiling water and it only lost 2 degrees over an hour....

**Orfy** · 02-20-2007, 09:50 PM

A mash has a better thermal buffer than plain water so you should be ok.

Jer · 02-20-2007, 09:58 PM

Quote:

Nice looking display screen, is this a visual basic application that you have built yourself to interface with the board in the picture.

I used Borland C++ Builder to create the app, and just use normal rs-232 serial to communicate with the board, although I'm kinda reading up on USB stuff, that way I could power the board through USB instead of an external power source..

Quote:

Do you have any plans to expand the scope of the application to include pumping and valve control in an expanded system?

I'm still thinking about adding some relays.. I originally wanted a little device that could control some fans so that I could blow cold air from outside into a little box when the temp in the box got too warm, so that I could lager over the winter, but I got distracted by needing a thermometer for mashing..

I've been looking on ebay for some heater elements and solenoid valves cause I thought it'd be pretty cool to automate the whole mash process.. Although I'm still pretty new to AG and am batch sparging, so I don't know if I should look into other methods if I'm going to automate it..

**kladue** · 02-20-2007, 10:06 PM

Is the interface on the board to computer a RS 232 or RS 485, and are you using 10K thermistors with a 5V drive voltage and 0-5V interface.

**Orfy** · 02-20-2007, 10:07 PM

Quote:

Originally Posted by kladue

Is the interface on the board to computer a RS 232 or RS 485, and are you using 10K thermistors with a 5V drive voltage and 0-5V interface.

That's just what I was thinking.

Jer · 02-20-2007, 10:32 PM

Just RS-232...

10k thermistor in series with a 10k resistor. Using a 0-5v for the Vref (10 bit a/d)which can get around .2 degrees accuracy (at the lower temps( <120F)) and maybe 1 to .5 degrees at the higher temps, since it's an NTC thermistor and isn't linear... If I scale it between 100F and 204F I can get almost .1 degree accuracy over that range, but then self heating and some other factors come into play with that kinda accuracy, so to avoid some extra work I round to the nearest degree...

Thread Tools
Show Printable Version Email this Page
Display Modes
Linear Mode Switch to Hybrid Mode Switch to Threaded Mode

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Better way to monitor fermentation	johnd4	General Beer Discussion	8	11-04-2009 05:26 PM
Temperature Monitor	N5629	DIY Projects	5	03-31-2009 04:54 PM
How do you monitor your gravity	Korben	General Techniques	11	12-29-2008 05:44 PM
LCD desktop monitor repair	CarlLBC	General Chit Chat	2	11-20-2008 03:47 PM
What is the best way to monitor fermentation temp?	Mr. Mojo Rising	Equipment/Sanitation	3	04-04-2007 09:42 PM